This invention relates to apparatus for the collection and transfer of liquids. More particularly, it relates to apparatus for the collection of waste motor oil in a portable tank and the transfer of the waste motor oil from the portable tank to a larger holding tank.
There are many businesses which provide oil changes for automobiles and trucks, such as dealers, gas stations, and more recently, quick change motor oil businesses. Quick change motor oil businesses provide rapid oil changes for motor vehicles, often in less than one hour's time. The growth of quick change oil businesses has been substantial in recent years as consumers have demanded that this service be provided quickly and efficiently.
Quick change oil businesses normally utilize a portable oil collection apparatus which includes a tank having a funnel attached to the top of the tank through an opening in the tank. The funnel includes a stem which extends through the top opening of the tank into the interior of the tank. When it is time to collect waste oil from the vehicle crank case, the funnel is raised so that the distance between the oil drain hole on the crank case and the funnel is minimal to avoid spilling the oil due to misalignment, and splattering. Usually the funnel, and thus the stem, is lowered when the tank is not in use. This apparatus is located directly below a position where the vehicle crank case is positioned during the oil change. Often this apparatus is used in a pit under the floor. When the crank case is opened, waste oil will drain into the funnel and thus into the portable tank.
Once the tank is full, it is important to be able to efficiently and quickly transfer the waste oil from the portable collection apparatus to a larger permanent waste oil holding tank which is normally located outside of the building and often above level of the portable tank which is in the pit. The portable tank includes an exit port valve located near the bottom of the tank. A hose is connected to the exit port valve and to the permanent holding tank when it is time to transfer the waste oil. It is desirable to be able to quickly transfer the waste oil from the portable tank to the permanent tank. The oil is sometimes transferred by injecting high pressured gas, such as air, into the portable tank. Often air pressures inside of the tank will be as much as 30 lbs. per square inch. Because the bottom of the stem inside the tank is always open to permit the oil to drain from the funnel into the inside of the tank, the path through the stem must be closed off when air pressure is applied to the tank, otherwise waste oil would blow back into the stem and out of the funnel.
Prior art portable collection tanks often utilize a hand-operated ball valve which includes a handle on the exterior of the tank near the top of the tank to open and close the passageway through the stem. That is, the valve is cranked open when it is time for the oil to drain through the funnel into the tank, and is cranked closed when it is time to pressurize the tank to transfer the oil to the permanent tank. This hand-operated ball valve adds substantial expense to the waste oil collection apparatus, and because the condition of the valve, i.e., opened or closed, is not readily apparent to the operator, accidents sometime occur when air pressure is applied to the tank and the valve is inadvertently left open.